FlagThis — Daily Cybersecurity Intelligence Briefing

Researchers from MIT CSAIL have discovered "Interrupt Injection," a sophisticated Time-of-Check to Time-of-Use (TOCTOU) vulnerability that bypasses Spectre v2 mitigations on Intel and AMD CPUs. The attack exploits a critical timing window where an unprivileged user can trigger a hardware interrupt immediately after the branch predictor has been sanitized but before the kernel executes. This allows for the re-poisoning of the branch predictor, enabling speculative execution-based data leakage across privilege boundaries. The discovery exposes fundamental weaknesses in current microarchitectural defense implementations, necessitating immediate kernel-level updates to secure Linux-based systems against cross-privilege information disclosure.

A systemic structural failure has been identified in the Remote Attestation mechanisms of Intel SGX/TDX, AMD SEV-SNP, and ARM TrustZone. Research, including the TEEFail analysis, reveals a fundamental decoupling between hardware identity proofs (Attestation Quotes) and the secure communication channels (Attested TLS). This gap allows attackers to execute relay attacks, where a "Fake Enclave" can spoof the identity of a secure environment, misleading the client into believing the session is hardware-isolated. This vulnerability invalidates the core premise of Confidential Computing by breaking the cryptographic binding between the hardware root of trust and the transport layer, exposing encrypted memory enclaves to Man-in-the-Middle (MitM) exploitation.